1. Field of the Invention
This invention relates to a fuel injection pump for use with diesel engines and, more particularly, to a distributor type fuel injection pump equipped with an automatic injection timing control device.
2. Description of the Prior Art
Fuel injection pumps have been used with diesel engines for operating them with varying the timing of fuel injection as a function of the frequency of rotation of the engine. It is desirable to assure stable engine operation over the full running range by controlling the injection timing in accordance with various engine operating parameters. For example, it is the common practice to give an advance to the injection timing during engine starting for high engine starting stability.
For this purpose, distributor type fuel injection pumps have been proposed for successively supplying pressurized fuel to engine injectors in synchronism with engine rotation. Such fuel injection pumps includes an angularly movable control member adapted to determine the timing of fuel injection in accordance with its angular position, and an injection timing control device for varying the angular position of the control member as a function of engine speed. However, such an injection timing control device suffers from certain disadvantages as described later in detail.
The present invention provides a distributor type fuel injection pump equipped with a simple and compact injection timing control device capable of controlling the injection timing with high accuracy and high response to engine operating conditions.